DELIMITER $$
CREATE  PROCEDURE `sp_add_Index`(
    IN p_tablename VARCHAR (100),  
    IN p_indexType VARCHAR(100),
    IN p_indexcolumnList VARCHAR (200),
    IN p_idxname VARCHAR(70)
)
BEGIN  

-- CALL `sp_add_Index`('sys_resource','unique','code','');
-- CALL `sp_add_Index`('sys_resource','index','parent_code','');
    DECLARE p_dbname VARCHAR(50);
    SET @p_dbname = DATABASE();
    SET @p_idxname = p_idxname; -- 索引名不能超過64位元組
    
    CASE p_indexType 
    WHEN 'primary' THEN
    SET @p_idxname = 'primary';
    SET @add_index = CONCAT('ALTER TABLE ', p_tablename, ' ADD ', 'primary key(', p_indexcolumnList ,');');
    WHEN 'unique' THEN
    IF LENGTH(@p_idxname) = 0 THEN
SET @p_idxname = CONCAT('uni_idx_',p_tablename,'_',REPLACE(p_indexcolumnList,',','_'));
END IF;
      SET @add_index = CONCAT('ALTER TABLE ', p_tablename, ' ADD ', p_indexType,' ',@p_idxname ,'(', p_indexcolumnList ,');');
    ELSE
    IF LENGTH(@p_idxname) = 0 THEN
SET @p_idxname = CONCAT('idx_',p_tablename,'_',REPLACE(p_indexcolumnList,',','_'));
END IF;
      SET @add_index = CONCAT('ALTER TABLE ', p_tablename, ' ADD ', p_indexType,' ',@p_idxname ,'(', p_indexcolumnList ,');');
     END CASE;
    SELECT  
COUNT(*) INTO @cnt  
    FROM  
information_schema.statistics  
    WHERE  
TABLE_SCHEMA = @p_dbname  
AND table_name = p_tablename  
AND index_name = @p_idxname;  
IF @cnt = 0 THEN  
PREPARE stmt FROM @add_index;   EXECUTE stmt; 
END IF;
END$$


DELIMITER ;